The French association SACEM, which controls royalties paid out to authors, announced last week that Apple has failed to pay 5 million euros ($6.5 million) in royalties and taxes on iPads sold in 2011.

To give a bit of a background, the ‘copie privée’ is a tax in several countries, including France and Germany, that is applied to all digital devices that can transfer, read, or otherwise make use of copyrighted material.

The tax goes to the SACEM, which then takes the lump sum of all the taxes collected and deals them out to authors, creators, producers, actors, etc. accordingly.

Now there are plenty of taxes in France – the latest for tablets may be a 1% tax to go to cultural works – but the problem here isn’t so much the tax, but that Apple actually charged the consumers this tax and didn’t pay it out to the SACEM.

This is a surprisingly absent-minded slip up for a company that prides itself on its low tax rates, and is getting attacked from all angles about taxes paid on revenues generated.

The overall point, however, is crystal clear: the government is thumbing through every page of major tech companies’ tax declarations, and now is not a good time to slip up on something simple like this.